"Kore, sore, are"
When we do not know the name of something, what do we use? We say "this thing" or "that thing"
right? Such is the case with kore, sore, and are.

We use kore to refer to something close to you (the speaker)
Ex: Kore wa watashi no enpitsu desu.
This (thing here) is my pencil.

Sore is used to talk about something that is close to the person you are talking to.
Ex: If I was talking with Cheri-sama, I would say "Sore wa watashi no enpitsu desu"
That thing (in front of you) is my pencil.

Are is used to talk about something that is neither close to the speaker nor the listener.
Ex: If Cheri and I were in a classroom and someone had my pencil across the room, I'd say "Are wa watashi no
enpitsu desu"
That thing (over there) is my pencil.

To ask about something:
Dore ga anata no enpitsu desu ka?
Which one is your pencil?

Notice how we use "ga" instead of "wa". Question words such a "dore" or "nani"
cannot be followed by "wa". Thus, we use "ga".

"Kono, sono, ano, dono"

The same rules apply for this set of words. You use these when you want to be more specific about something.

Ex: Kono kaban wa ikura desu ka?
How much is this bag?

At which point the shop owner would say,
"Sono kaban wa sansen en desu"
That bag is 3000 yen.

And if you were talking about a bag on the other side of counter, well...
Ano kaban wa sanzengohyaku en desu.
That bag over there is 3500 yen.